This invention relates to a split nut assembly which is designed to be mounted on a threaded stud or shaft without passing over the end of the stud or shaft.
Nuts and threaded studs or shafts are extensively employed in virtually every technology involving mechanical configurations. The simple nut and threaded stud or shaft for attaching two or more parts, with the free end of the stud or shaft exposed is a common arrangement in which the nut can readily be mounted and removed.
In more complex arrangements, however, as found in piping supports in construction and in machinery, the stud or shaft may perform a variety of functions, such as connecting together two or more assemblies at different locations, or the nut and stud or shaft may not only connect together plates or walls, but the stud or shaft may not be threaded over its whole length.
It is readily seen that in a complex arrangement the necessity to remove a conventional nut would ordinarily involve the removal of all elements on the stud or bolt starting from the free end to get to the particular nut which requires removal.
This problem is not new, and a variety of efforts have been made to overcome this difficulty, including the use of a split nut which can be mounted and removed without passing over the free end of the stud or bolt.
An example of a split nut designed for such application is shown in U.S. Pat. No. 4,274,323 which illustrates a variety of split nut configurations. In FIG. 21 of that patent there is shown a split nut having two pairs of split washers 204 which engage with the former to hold it together as it is tightened. This assembly has six parts, while another arrangement shown in FIG. 2 consists of four parts.
An important drawback of the split nut assemblies shown in the aforementioned U.S. patent is the distortion in the washer which can occur when the nut is tightened. As the nut is being tightened in place, the washer parts are rotated through projections which engage grooves in the nut parts. As the washers presumably are tightened against a surface or wall being clamped, it is seen that the washer can be distorted, and if the nut is tightened enough, presumably the projections could be torn loose or sheared. In addition, as the washers are annular so that both the washers and nuts presumably may contact the wall, there is some question as to the effectiveness of the arrangement.